Medial rotation deformity of the hip in cerebral palsy: Surgical treatment by derotation femoral osteotomy

Medial rotation deformity of the hip is a problem to patients handicapped by cerebral palsy who are able to walk, because the knees point inward during gait ("kissing patellae") and cause falls and frequent injuries, knee and ankle distorsions. The deformity is a result of an increased femoral neck anteversion. The purpose of the paper is to present the results of an original method of precise determination of the degree of rotation for derotation femoral osteotomy. Indications for this operation were set in patients with spastic form of cerebral palsy over 10 years of age, able to walk, who had difficulties in gait and whose lateral rotation was less than 15 along with the medial rotation of over 70 in the hip on the side of the deformity. Twenty hips in 17 patients able to walk were operated on. The average age was 21 (11 - 42), the average follow-up was 11 years (3-17). The assessment of the results was based on the comparison of the rotational abilities of the hip and individual problems before and after the operation. Excellent result was achieved in 12 (70.6%) patients i.e. 15 (75%) hips; good result was achieved in 3 (17.6%) patients i.e. 3 (15%) hips; unsuccessful result in 2 (11.8%) patients i.e. 2 (10%) hips. Complications aroused in 6 patients i.e. 6 (30%) hips. The conclusion is that derotation osteotomy of the femur is a successful procedure for the treatment of the medial rotation deformity of the hip in patients with the spastic form of cerebral palsy who are able to walk. The above mentioned indications must be respected and the original method of determining the degree of derotation applied. Due to a relatively high percentage of complications, e.g. osteitis, the operation is suggested to patients aged 10 to 15 when possible complications can more easily be cured.